hello all I have a 05 LLY crew cab long bed. I was wanting to put a single stack in the bed but i have a stock exhaust. I want to get rid of the cat and run a straight pipe. my Q: is can i run a factory to the bed then put expanders up to 6'' stack?? or do I need to run a 4'' to the stack? any info would be a great help.

Sure you *can*. Should you? I don't think I would. 4" frontpipes can be had for a little more than $100, then some flex, a 90*, some clamps and you're set. :D

excatly what SmokeShow said you can use adapters to use the stock stuff but 4" pipe is cheep and since your gona be under there might as well go all the way lol

smokeshow where do you get the 4'' front pipe?

MBRP sells the front pipe. Check to see if any of the Vendors sell MBRP.